Quick acting contact coupling

ABSTRACT

A quick-acting contact coupling for making a fluid-tight connection between a source of pressurized fluid and a work member, such as a fuel pump. A pressure actuated mechanism including a piston member having a contact sealing member connected thereto accomplishes a quick fluid-tight connection between the coupling assembly and the work member without the use of threaded fasteners or connectors. The contact sealing member has a hardened tip portion and a relatively flexible stem portion which allows minute alignment adjustments between the sealing and work members.

United States Patent [191 Dawes [111 3,826,522 1 July 30, 1974 Attorney, Agent, or Firm-Phillips, Moore, Weissen- [75] Inventor: Stanley G. Dawes, Oakland, Calif. berger, Lempio & Strabala [73] Assignee: Caterpillar Tractor Co., Peoria, 111. 22 Filed: Apr. 28, 1972 L t k ABSTRATCT f H quic -actmg contact coup mg or ma mg a U1 [21 1 Appl' 248,606 tight connection between a source of pressurized fluid and a work member, such as a fuel pump. A pressure [52] U.S. Cl. 285/18, 285/9 actuatfid mechanism including a Piston member 51 im. Cl. F16! 35/00, F16] 28/50 ing a Contact sealing member connected thereto [58] Fi ld f S a h 285/9, 18 33 3344 DI 21 complishes a quick fluid-tight connection between the coupling assembly and the work member without the [56] References Ci d use of threaded fasteners or connectors. The contact UNITED STATES PATENTS sealing member has a hardened tip portion and a rela- 590 423 6 I 926 C tively flexible stem portion which allows minute align- 5 5'2) 411930 g gz 622 2 ment adjustments between the sealing and work mem- 3,233,549 2/1966 Howe 285/9 R x 11 Claims, 2 Drawing Figures l QUICK ACTING CONTACT COUPLING BACKGROUND OF THE INVENTION Present methods for testing fuel pump assemblies, as part of a quality control program in the manufacturing process, require that a fuel line be secured between each pump outlet and a testing apparatus. This closely simulates the actual connection of fuel lines to the pump in the final assembly of the pump to an engine.

Such attachment of a plurality of lines to the fuel pump is very time-consuming since each connector line must be screw-threadably fastened to acorresponding threaded extension of the fuel pump. Six to eight individually threaded connections must, therefore, be made to each pump, depending upon the type being tested.

Additionally, the fuel line connector probe of the testing apparatus generally contacts the seat portion of the pump extension at approximately the same location as will the fuel line connector in the final engine assembly. This often causes scoring or marring of the seating surface which later leads to a leaking fuel line in the final engine assembly.

OBJECTS OF THE INVENTION Accordingly, it is an object of the present invention to provide an improved quick-acting contact coupling which does not require a threaded connection.

Another object of this invention is to provide such a coupling which accomplishes a fluid-tight seal to a work member without causing damage to the work member.

Yet another object is to provide such a coupling which is flexible to. provide for minute alignment adjustments.

A still further object of this invention is to provide a saving of time and effort in the process of testing fuel pump assemblies.

Other objects and advantages of the present invention will become more readily apparent upon reference to the accompanying drawing and following description.

. BRIEF DESCRIPTION'OF THE DRAWING FIG. 1 is a front elevation, partially in section, showing a quick-acting contact coupling embodying the principles of the present invention associated with a fuel pump to be tested.

FIG. 2 is a somewhat enlarged sectional view of the connection between the quick-acting contact coupling of the present invention and the fuel pump which further shows a prior art connector in broken lines.

DETAILED DESCRIPTION Referring more particularly to the drawing, a quickacting contact coupling embodying the principles of the present invention is indicated generally by reference numeral 10. The coupling includes a body 11 having a plurality of fluid cylinders, a chamber formed by one of which is indicated by reference numeral 12. A hollow piston assembly 13 is contained within each of the fluid cylinders and reciprocates in response to fluid pressure, usually hydraulic, which is introduced into the cylinder by means of conduits and a pressure fluid supply means such as a pump (not shown).

The hollow piston assembly 13 includes a rod portion 14 having an internal axial passageway 17, and a piston portion 18 having sealing rings 19 and 20. The piston portion forms a second chamber within the cylinder. The piston assembly further includes a hollow probe or extension portion 21 which has an internal axial passageway 22 which communicates with internal passage 17. The extension has a frustoconical mounting end 23 which is releasably secured to a correspondingly frustoconically recessed end portion 24 of the rod portion by means of a threaded connector 25. The connector 25 has an annular flange portion 50 which coacts with a flange 51 on the extension 21, as shown. An annular torus-shaped contacting surface 26 is integrally formed on the distal end of the extension member and serves to seal one end of a fluid flow path formed by the passageways 17 and 22. The opposite end of the fluid path is connected in sealing relation to a fluid line 27 connected to a source of pressurized fluid (not shown) by a threaded connector 28.

The piston assembly 13 is selectively moved to its extended position, shown in FIG. 1, by means of the introduction of pressurized fluid into the cylinder chamber 12 by way of a conduit 31 and a port 32. It should be understood that the conduits of the instant coupling assembly are provided with suitable valve means to accomplish the purpose intended. The piston assembly is moved to a retracted position by means of the controlled introduction of pressurized fluid to the chamber 15 by way of a conduit 33 and a port 34. All of the piston assemblies 13 of the quick acting coupling10 are extended or retracted simultaneously due to the connection of all the cylinders by means of a plurality of sets of internal passages 35 and 36.

The quick-acting contact coupling serves to make a plurality of fluid-tight connections to a fuel pump assembly, a portion of which is shown in the drawing and indicated by reference numeral 39. The pump assembly contains a plurality of connector threaded portions which extend outwardly thereof with each connector portion having an internal passage 41. Each connector portion is provided with an external thread 42 and an inner frustoconical seating portion 43. When the hollow piston assemblies 13 are extended,'as shown in FIGS. 1 and 2, the contacting surface 26 of each extension member 21 engages the seating portion 43 of the pump assembly and immediately forms a fluid-tight seal therewith.

Since the extension member 21 is secured to the rod portion 14 by means of a threaded connector 25, it is a simple matter to remove the connector and replace the extension member with one of a different size or type. In this manner, various sizes and types of fuel pump assemblies can be tested with the quick-acting coupling 10 by merely replacing the hollow extension member 21. The contacting surface 26 of the extension member 21 is preferably heat treated to a hardness greater than that of the remainder of the member. In particular, the hardness value of the contacting surface is preferably within the range of Rockwell C60 and the remainder of the extension member is within the range of Rockwell C-3844. Such a harder contacting surface insures a better seal against the fuel pump assembly seating portion 43 as well as a long service life for the contacting part despite repetitive utilization. The relatively less hard condition of the remainder of the extension member allows it to flex minutely in the 3 event that a minor misalignment is encountered be tween the extension member and the fuel pump assembly. it should also be "noted that assembly can be adapted to absorb a limited amount of recoil which might be encountered upon extension of the member 21. This can be accomplished by controlling the pressure within chamber 12 and by the utilization of gas as the pressurizing fluid.

The sealing relationship between the contacting surface 26 and the seating portion 43 is best seen in FIG. 2 of the drawingFlG. 2 also shows, in broken lines, a prior art connector-46 and its associated seating'probe 47. The prior art connector is fastened to the fuel pump connector portion 40 by means of the thread 42 and the seating probe is sealed against the inner seating portion 43.

It will be readily seen that the point of contact between the contacting surface 26 of the present coupling and the seating portion 43, which point is indicated by the reference numeral 48 is substantially below the lowest extent of the area of contact between the prior art seating probe and the seating portion 43, indicated by reference numeral 49. The position of the prior art seating probe also represents the position of a standard fuel line tip when a fuel line-of an engine is attached in actual operation of the fuel pump. Therefore, any mark which is left on the seating portion 43 from the contact ing surface 26 will have no effect on a future fuel line seat.

i OPERATION At the beginning of an operation for connecting the quick-acting contact coupling 10 to the fuel pump assembly 39, the hollow plunger assemblies 13 are in a retracted position and there is no connection between the extension 21 and the pump connecting portions 40. In order to test the fuel pump assembly, a fluid tight connection must be made between the quick-acting contact coupling and the fuel pump assembly.

To accomplish this connection, pressurized fluid is introduced. into the cylinder 12 by way of the fluid line 31 and the port 32. The fluid pressure acts upon the piston 18 and forces the hollow plunger assembly 13 outwardly of the body 11. As the plunger assembly is extended, the contacting surface 26 of the extension member 21 engages the inner seating portion 43 of the fuel pump. connector portion 40 in tightly fluid-sealing relation. Due to the pressure developed in the cylinder chamber 12, such engagement between the contacting surface and the seating portion maintains a'fluid-tight seal between the passage 41 and the passageway 22. As noted above, if a resilient recoil capability is desired, such as in cases where high-speed, repetitive testing is required, gas under controlled pressure would be admitted tochamber 12 instead of hydraulicfluid which would normallybe utilized.

When the testing operation is completed, the quickacting contact coupling 10 is quickly and easily disconnected from the fuel pump assembly 39. This is accomplished by introducing pressurized fluid into the underpiston cylinder chamber 15 by way of the conduit 33 and the port 34. The pressurized fluid entering the cylinder chamber acts upwardly upon the piston 18 and retracts the piston assembly 13 into the body 11. Since the extension member 21 is fastened to the piston assembly, it too is retracted and the sealing connection between the contacting surface 26 and the seating porfluid-tight seal between a source of pressurized testing fluid and a work member and which does'not cause damage to the work member'while providing an effecient, relatively simple testing operation.

While the invention has been described and shown with particular reference to the preferred embodiment, it will be apparent that variations are possible which would fall within the spirit of the present invention which is not intended to be limited, except by the scope of the appended claims.

1 claim:

1. A quick-acting contact coupling for simulating the operative sealing connection of a fluid line to a work member having a connector portion including a seat portion which coupling comprises; body means adapted to be disposed in spacedrelation to such a work member, hollow piston means disposed within said body means for connection to a first source of pressurized fluid, said piston means including a first hollow, interior portion in fluid communication with said first source, said piston means being reciprocably mounted within said body means and powered by actuating means for movement between an extended position wherein contact is made between said hollow piston means and said work member and a retracted position wherein said piston means is apart from said work member, and sealing means carried upon a portion of said piston means and being movable therewith for engagement with said seat portion in fluid tight sealing relation therewith when said piston means is moved to said extended position said sealing means comprising a hollow extension member separate from and releasably secured to said portion of said piston means and having contacting surface means for engaging said seat portion in fluid tight sealing relation thereto, said hollow extensionmember having a second hollow interior portion in direct fluid communication with said first hollow interior portion for communicating said source with said work member.

2. The invention of claim 1 wherein said hollow extension member comprises an elongated tubular probe having a frustoconical end for mounting in sealing engagement upon said hollow piston means.

3. The invention of ;claim 2 wherein said contacting surface means includes a torus-shaped element formed upon an end portion of said tubular probe 'which is opposite to said frustoconical mounting end.

4. The invention of claim 3 wherein saidtorus-shaped contacting element is conditioned to a harder metallurgical state than is the remainder of said tubular probe and wherein said tubular probe includes a frustoconical portion immediately adjacent to said torus-shaped element. v

5. The invention of claim 4 wherein said torus-shaped contacting element is adapted to engage said seat portion at a first contact point which is axially spaced from a second contactpoint normally formed between said 7 fluid line'and said seat portion such that any mark left on said seat portion by said element will not derogate an operative sealing connection between said fluid line and said seat portion at said second contact point.

6. The invention of claim 5 wherein said hollow extension member is readily removable and interchangeable with a plurality of extension members having various sizes and shapes for accommodating work members having various corresponding sizes and shapes.

7. The invention of claim I wherein said actuating means include a source of actuating fluid under pressure which acts upon said piston means to forcibly move said piston means selectively toward said extended position or said retracted position.

8. The invention of claim 7 wherein said actuating means include a second source of pressurized gas for resiliently holding said piston means in said extended position and absorbing any recoil therefrom.

9. The invention of claim 7 wherein said body means include conduit means for communicating said fluid under pressure to said piston means for actuation thereof.

10. The invention of claim 1 wherein said piston means include a rigid piston member mounted for reciprocation within bore means of said body means, said rigid piston member having annular means mounted thereon for sealing between said piston member and said bore means, said bore means being divided by said sealing means into first and second chambers, said piston member being movable to said extended position upon admission of pressurized fluid to said first chamber while exhausting said second chamber and to said retracted position upon admission of pressurized fluid to said second chamber while exhausting said first chamber.

11. The invention of claim 1 wherein said body means include a plurality of bores and wherein said piston means include a plurality of piston members mounted for simultaneous reciprocation within said plurality of bores 

1. A quick-acting contact coupling for simulating the operative sealing connection of a fluid line to a work member having a connector portion including a seat portion which coupliNg comprises; body means adapted to be disposed in spaced relation to such a work member, hollow piston means disposed within said body means for connection to a first source of pressurized fluid, said piston means including a first hollow interior portion in fluid communication with said first source, said piston means being reciprocably mounted within said body means and powered by actuating means for movement between an extended position wherein contact is made between said hollow piston means and said work member and a retracted position wherein said piston means is apart from said work member, and sealing means carried upon a portion of said piston means and being movable therewith for engagement with said seat portion in fluid tight sealing relation therewith when said piston means is moved to said extended position said sealing means comprising a hollow extension member separate from and releasably secured to said portion of said piston means and having contacting surface means for engaging said seat portion in fluid tight sealing relation thereto, said hollow extension member having a second hollow interior portion in direct fluid communication with said first hollow interior portion for communicating said source with said work member.
 2. The invention of claim 1 wherein said hollow extension member comprises an elongated tubular probe having a frustoconical end for mounting in sealing engagement upon said hollow piston means.
 3. The invention of claim 2 wherein said contacting surface means includes a torus-shaped element formed upon an end portion of said tubular probe which is opposite to said frustoconical mounting end.
 4. The invention of claim 3 wherein said torus-shaped contacting element is conditioned to a harder metallurgical state than is the remainder of said tubular probe and wherein said tubular probe includes a frustoconical portion immediately adjacent to said torus-shaped element.
 5. The invention of claim 4 wherein said torus-shaped contacting element is adapted to engage said seat portion at a first contact point which is axially spaced from a second contact point normally formed between said fluid line and said seat portion such that any mark left on said seat portion by said element will not derogate an operative sealing connection between said fluid line and said seat portion at said second contact point.
 6. The invention of claim 5 wherein said hollow extension member is readily removable and interchangeable with a plurality of extension members having various sizes and shapes for accommodating work members having various corresponding sizes and shapes.
 7. The invention of claim 1 wherein said actuating means include a source of actuating fluid under pressure which acts upon said piston means to forcibly move said piston means selectively toward said extended position or said retracted position.
 8. The invention of claim 7 wherein said actuating means include a second source of pressurized gas for resiliently holding said piston means in said extended position and absorbing any recoil therefrom.
 9. The invention of claim 7 wherein said body means include conduit means for communicating said fluid under pressure to said piston means for actuation thereof.
 10. The invention of claim 1 wherein said piston means include a rigid piston member mounted for reciprocation within bore means of said body means, said rigid piston member having annular means mounted thereon for sealing between said piston member and said bore means, said bore means being divided by said sealing means into first and second chambers, said piston member being movable to said extended position upon admission of pressurized fluid to said first chamber while exhausting said second chamber and to said retracted position upon admission of pressurized fluid to said second chamber while exhausting said first chamber.
 11. The invention of claim 1 wherein said body means include a plurality of bores and wherein said piston means include a plurality Of piston members mounted for simultaneous reciprocation within said plurality of bores. 